Custom Fit Knee™ Replacement
Comparison with Other Techniques
Techniques in total knee replacement have remained fairly consistent over the past few decades, although some surgeons have begun to explore new minimally invasive and computer-assisted approaches.
However, none of these new approaches takes into account the very individual nature of knee anatomy and the impact this can have on the knee replacement procedure.
Here is a comparison of traditional and the new Custom Fit Knee™ replacement with OtisKnee™ guide.
Traditional Total Knee Replacement
Approach:
In traditional knee replacement, the surgeon uses a “one size” fits all approach, meaning that the overall fit and placement of the implant is similar for each patient. Any individualization that is done occurs during surgery, based on the anatomy that is visible to the surgeon. This includes decisions on where and how much bone to cut as well as how to balance the ligaments that surround the new knee.
Risks:
Traditional surgery requires that the surgeon drill an intramedullary (“IM”) rod into the patient’s femur, or thigh bone, to aid in proper alignment. When an IM rod is used, it puts the patient at increased risk of cardiopulmonary complications caused by fat particles (from the bone marrow) entering the blood stream. It also increases risk of blood loss and infection. In addition, more bone and a key ligament called the “posterior cruciate” is often cut during traditional surgery. This can cause the new knee to feel unnatural.
Outcomes:
With traditional total knee replacement, patients typically stay in the hospital for a minimum of three days. And some are sent to a rehabilitation facility before returning home. Most patients are walking without a cane or walker by 6 weeks, with a return to normal activities (driving, gardening, etc.) by 12 weeks. Average range of motion to be expected six months from surgery is 109°, although scarring of the knee can occasionally occur and motion may be more limited*. Medications are often needed to manage pain throughout recovery.
* Matziolis, G, et al., “A Prospective Randomized Study of Computer-Assisted and Conventional Total Knee Arthroplasty. Three-Dimensional Evaluation of Implant Alignment and Rotation,” JBJS, 2007:89:236-243
Custom Fit Knee™ Replacement with OtisKnee™ Guide
Approach:
With Custom Fit Knee™ replacement, the surgeon matches the size and placement of the implant to each particular patient. Instrumentation and implants are pre-planned, based on the patient’s normal (non-diseased) knee anatomy. This means that the surgery can be done accurately and quickly, with less intra-operative decision making required from the surgeon. No IM rod is used, as the custom fit technology is all that is needed to ensure proper alignment. In addition, less bone is cut and all ligaments are spared, preserving the feel of a more “natural” feeling knee based on the patient’s normal knee function.
Risks:
While all surgical procedures involve risk, Custom Fit Knee™ replacement was designed to minimize the risks often seen with traditional and computer-assisted techniques. With the custom fit approach, patients spend less time under anesthesia, have no additive risk of cardio-pulmonary complications (caused in traditional surgery by the IM rod) and have up to 40% less bone removed from the femur (thigh bone). They have also reported less post-operative pain.
Reported Outcomes:
“With OtisKnee™ guide, my patients are reporting significantly less pain both after surgery and throughout their recovery. I have also seen a great increase in their flexion and range of motion. This means they are able to return to daily living activities more quickly. Most patients are off of a cane or walker by as early as 2 to 3 weeks and are able to return to activities such as driving, gardening and golfing by as early as 6 weeks.”
– Stephen Howell, M.D.
OtisKnee™ guide and Custom Fit Knee™ replacement are not prosthetic devices that are implanted in the knee and replace part of the knee joint when knee replacement surgery is performed. OtisKnee™ guide is a custom cutting guide used during the surgery to assist the surgeon in making very accurate bone cuts that are specific to the individual patient. It does not remain in the body after surgery. Custom Fit Knee™ replacement is a technique or procedure that allows the surgeon, before surgery, to match the size and placement of the implant to the patient's normal (non-diseased) anatomy. The surgery can then be done accurately and quickly, with less intra-operative decision-making required on the part of the surgeon.
